With the advent of networking technology, the ability to access information from distal sources has greatly increased. The explosive growth of the World Wide Web and commercial on-line networks and information sources are indicative of the high demand for accessing information. However, it is typical that such access is not instantaneous. For example, an operation for obtaining copies of information may require a period of time longer than the user may want or have. It is beneficial for a user to know how much time is required for performing an operation on a distal source, as well as the progress of the operation being performed.
The notion of a progress feedback indicator has been widely incorporated into both user and program interfaces. Many application programs provide upfront feedback on estimated time for an operation, e.g. the Norton Backup product available from the Symantec Corporation presents an estimated time to perform a backup. Installers for installing application software programs on personal computers provide feedback on the progress of an installation of the software applications. Print managers typically report status of printing requests (e.g. sending/printing/completed).
Almost all serial upload and download programs (e.g. on-line services like America On-Line and Compuserve) estimate how long file and message transfers will take and provide progress reports. They use the connection rate (e.g. 14400 bps) to estimate an initial transfer time, and then they continually measure the actual bytes/second as the transfer is underway. This mode of transfer now runs almost identically over networks (e.g. via the Mac Communications Toolbox) so there is now a class of network file clients that provides such information. However, this method does not take into account various factors such as current network traffic and any delays that may be incurred at either the source or the recipient.
An architecture for a system for interacting with distal information sources is described in the article "System Components For Embedded Information Retrieval From Multiple Disparate Information Sources", Rao et al., Proceedings of the ACM Symposium on User Interface Software and Technology, ACM press, (November 1993). With respect to interacting with such distal information sources, various operations may be performed (e.g. searches or download of information). Such operations tend to be long-running. If a user knowingly executes a long-running operation, they are able to remain productive by performing some other task. Further, progress feedback provides a user with reassurance that the requested operation is being performed. Thus, it is desirable to obtain accurate time estimate and progress information related to the execution of such operations